The present invention relates to a female fitting and the pipe connection in which a male fitting is engaged in said female fitting, the engagement ensuring the opening of a valve provided on at least one of these elements, the valve being of the rotating ball type.
A valve of this type has a closure element of generally spherical shape, made as a horseshoe and comprising millings or piercings so as to position the closure element. This spherical closure element is mounted in a connecting element or male fitting or female fitting with its center coinciding with the axis of the channel for passage of the fluid to be controlled, this spherical closure element, which bears against a seat at the outlet of the channel in the valve chamber comprising a diametrical bore, which can by suitable means be brought into coincidence with the channel for the fluid to ensure opening of the valve or to be oriented substantially 90xc2x0 to ensure closing of the valve.
A spherical closure element of this type comprises a rotation means such as two balls or a transverse shaft which is arranged to coact with a sleeve having the shape of a hollow shaft and which directs the fluid stream, the sleeve being prolonged at one end by a member such as an arm or a rod which is articulated on the rotation member. A fitting also comprises a cylindrical ring defining at its external end a bearing seat and the sealing in the cylindrical body and against which comes to bear the spherical closure member drivable in translation in the fitting according to the paths determining the conditions of opening and closing of the closure element, the assembly of these elements being enclosed in a concentric cylindrical body.
Such a connection is known from FR 2.521.685 in which the valve comprises a fixed axial sleeve disposed at the rear of the body of the fitting, directed toward the outlet of the connection and traversed by the passage of the connection, this sleeve comprising at its inner end corresponding to the rear of the body, a support for a return spring and at its external end, on the side of the connection region, a radial flange whose two lateral surfaces are tangent to the external surface of the sleeve, a chamber opening into the sector in the spherical region opposite to the active sector being provided in the spherical closure element, this chamber comprising surfaces cooperating in sliding contact with the side surfaces of the flange of the sleeve and the axle for driving in rotation the closure element being carried by the flange of the sleeve and perpendicular to said surfaces.
This type of pipe connection is used in hydraulic fields, in armament and in the field of space. In particular, it is used as a pipe connection for the fueling of vehicles. In the case of racing vehicles or military vehicles, it is desirable that the refueling take place as rapidly as possible and in a sure manner thereby guaranteeing perfect security of the connection.
Thus, in the case of use in automotive competition for example, the emplacement of the connection for refueling with gasoline must be carried out as rapidly as possible and with all security so as to avoid spilling gasoline on the brakes of the vehicle which would cause the vehicle to catch fire.
Present connections must be positioned correctly which is to say that the male fitting, or fueling fitting, must be presented to the female fitting, generally carried on the vehicle in the gas tank of the latter, perfectly along the axis to permit sure emplacement. This is not always easy to carry out on the one hand because of the weight of the material used, in particular when gravity fuelling is used, and on the other hand because of the conditions of use which can be difficult, as the fueling of a racing vehicle, mid-air fueling of an aircraft, etc.
The present invention has for its object to overcome this drawback by providing a new type of female fitting and a pipe connection of the type comprising a male fitting engaged in said female fitting, the engagement ensuring the opening of a valve provided on at least one of these fittings being permitted even if the constituent elements of one and the other are not perfectly aligned.
To this end, the invention has as its object a female fitting for a pipe connection adapted to be carried on a receiving structure such as a pipe or a reservoir, of the type comprising a cylindrical body within which is disposed concentrically a sleeve defining the fluid channel and carrying at its external end, articulated in rotation, a spherical closure element having a diametral bore, a cylindrical ring surrounding said sleeve and the spherical closure element being disposed drivably in translation in the cylindrical body against the force of resilient return means, the translatory paths of the ring in the body giving rise to driving in rotation of the spherical closure element between its opening position in which its bore coincides with the fluid channel and its closed position, characterized in that the sleeve and the cylindrical ring of this female fitting are mounted oscillably in the body of said fitting.
Thus, preferably, when the engagement of a male fitting is carried out with this female fitting, the freedom of oscillation of the sleeve and of the cylindrical ring in the body of the female fitting permit the assembly of the elements to assume the same axis to guarantee correct and sure connection, even if this engagement has a defect of alignment.
The internal end of the sleeve of the female fitting, which is to say the end of the sleeve turned toward the pipe or more precisely toward the gas tank in the case of an onboard fitting, has spherical bearing surface that bears against a complementary bearing surface of the internal end of the cylindrical body of the fitting in the manner of a swivel joint whilst the outer end of the cylindrical ring has a peripheral spherical bearing surface that bears against a bearing surface of complementary shape on the external end of the cylindrical body.
In this way, the spherical bearing surfaces of the sleeve and of the external end of the ring permit, by sliding against the complementary bearing surfaces of the cylindrical body, an oscillation of said sleeve and of the ring relative to the principal axis of the female fitting, to permit alignment of these members with those of a male fitting which does not lie on the same axis.
So as to promote sliding of the sleeve relative to the cylindrical body during oscillation, the internal end of the body and the internal end of the sleeve are treated to improve the sliding between said ends, with a treatment such as that known commercial as xe2x80x9cMicroflonxe2x80x9d.
Preferably, at least one of the bearing surfaces of the internal end of the cylindrical body or of the internal end of the sleeve, comprises at least one ball bearing surface. The sliding of said bearing surfaces is thus improved.
As a modification, the bearing surface of the internal end of the cylindrical body comprises wells spaced regularly angularly about said spherical bearing surface and containing each a ball, a well having a central curved surface and a peripheral conical surface. There is thus ensured an automatic re-centering during oscillation.
The cylindrical ring of each fitting defines at its external end, on the side of the connection region, a sealing and bearing seat for the spherical closure element, also called a joint capture cross-piece which serves for the creation of a trapezoidal throat to receive a joint. This sealing and bearing seat provides in the female fitting the peripheral spherical bearing surface.
The resilient return means permitting sliding in translation of the cylindrical ring within the cylindrical body of the female fitting is preferably a spring mounted between the cylindrical ring and the sleeve. Preferably, this resilient return means is disposed between the external end of the cylindrical ring which it maintains in sealed bearing relationship with the cylindrical body and the internal end of the sleeve which it maintains in bearing relation on the cylindrical body. The ring and the sleeve are thus connected and can oscillate together within the cylindrical body.
The sleeve of the female fitting is preferably short, which permits a saving in size and weight of the female fitting. This is particularly advantageous when the female fitting is onboard a race car for example.
According to a preferred embodiment of the invention, the spherical closure element of the fitting is made to horseshoe shape and comprises moreover two diametrically opposed flats provided respectively on an axis and on a cylindrical casing having sectors made in fork shape is disposed concentrically to the interior of the cylindrical ring, the axles of the spherical closure element being disposed in said forks, the fingers of the forks entering into recesses provided in the thickness of the seat for sealing and bearing under the influence of a resilient return means such as a Belleville washer or the like disposed between said cylindrical casing and the internal end of the cylindrical ring.
In this embodiment, the center of the spherical element is strictly invariable no matter what axis is considered, its centering within the fluid stream separates it from any risk of parasitic friction. Thus the strength of the assembly during oscillation is promoted.
So as further to promote the engagement of a male fitting and a female fitting which can be rendered difficult because of the weight and the rigidity of the tubing to which the male fitting is connected, there can be emplaced between the receiving structure of the female fitting and the cylindrical body of said female fitting, a bellows which permits mating with the extreme angular positions.
The present invention also has for its object a pipe connection of the type comprising a female fitting according to the invention and a male fitting comprising a cylindrical body within which is disposed concentrically a sleeve defining the fluid channel and carrying at its outer end, articulated in rotation, a spherical closure element having a diametrical bore, a cylindrical ring, surrounding said sleeve and the spherical closure element, being disposed drivably in translation in the cylindrical body against the force of a resilient return means, the translatory paths of the ring within the body giving rise, during engagement of the male fitting on the female fitting, to the driving in rotation of the spherical closure element between its open position in which its bore is brought into coincidence with the fluid channel, and its closed position, characterized in that the sleeve of the male fitting provided at its external end with the spherical closure element and surrounded by the cylindrical ring, is mounted projecting from the cylindrical body and the male fitting moreover comprises a casing engaged between the cylindrical ring and the cylindrical body, sliding in translation in said cylindrical body, a resilient return means being interposed between the cylindrical body and the front surface of said casing which ensures the engagement against the female fitting.
Thus, the ring and the casing constitute a portion in the form of a piston for engagement on the female fitting.
Preferably, the spherical closure member of the male fitting is made as a horseshoe and comprises moreover two diametrically opposed flats provided respectively with an axle.
In the male fitting, the sleeve has at its end a cylindrical casing having sectors made in horseshoe shape in which are disposed the axles of said spherical closure element so as strictly to control the centering of said spherical closure element, a resilient return means being interposed between the cylindrical casing and the sleeve.
During engagement of the male fitting on the female fitting, sealing is ensured by the emplacement of the casing on the facade of the female fitting. Preferably, the front engagement surface of the casing is made in the form of a trumpet-shaped cone which promotes a blind engagement for bringing together the fronts of the male and female fittings constituting the interface between the fittings.
According to a preferred embodiment, the connection according to the invention comprises a second circulation circuit substantially concentric with the fluid channel, for example for collecting gas.
Thus, the cylindrical ring of the male fitting has at least two peripheral lobes which define passages between said ring and the casing, said passages communicating with an evacuation conduit opening into the cylindrical body of the male fitting whilst the cylindrical body of the female fitting comprises openings which, during connection between the male fitting and the female fitting, are placed in communication with the passages of the male fitting.
During emplacement of the connection according to the invention, a circuit separate from the fluid channel is thus established between a gas tank or conduit in which is mounted the female fitting and an evacuation conduit opening into the male fitting and in which is established a circulation through openings of the cylindrical body of the female fitting and passages defined by the lobes of the cylindrical ring of the male fitting, toward the pipe.
Thus, a connection according to this embodiment of the invention forms, during engagement of the male fitting on the female fitting, a closed passage which can serve for collecting gas and can be preferably used in the case of fueling with evaporable fluids such as compressed gas of which liquefied natural gas (cryogenic), combustibles and generally speaking all liquids which, stored, have both a liquid phase and a vapor phase.
When the interface has been established by engagement of the front engagement surface of the casing of the male fitting on the front surface of the female fitting, the bearing seat and the seal of the male fitting come to bear against the bearing seat and seal of the female fitting and press the latter back into the cylindrical body of the female fitting. The seal within the female fitting is broken and a passage is opened for the gas from the gas tank or pipe through openings of the female fitting. The release of gas from the gas tank thus commences, the gas is then passing into the passages defined by the lobes of the cylindrical ring of the male fitting, toward the conduit opening into the male fitting, such that there can thus be a collection of the gases.
The return of the cylindrical ring of the female fitting also permits progressive opening of its spherical closure member. Once the gas tank is fully open, the ring bears against the rear end of the female fitting, and abuts under the influence of the pressure of the operator, arising during return of the cylindrical ring of the male fitting in the cylindrical body of said male fitting which gives rise to the opening of the spherical closure element of the male fitting.
To avoid small quantities of combustible interfering with the gas flow, torque joints (static sealing) are disposed on the one hand on the conical shoulder of the interface and on the other hand in the rear base of the onboard connection.
Preferably, the casing of the male fitting has openings permitting visualizing, preferably over 360xc2x0, of the filling by the operator, by noting the rise of bubbles preceding the filling of the gas tank, and the possible resulting overflow from overfilling.
This device, constructed such that the casings and rings have staged diameters, permits the production of a mechanical assembly in which the risks of wedging are avoided.
Preferably, the translatory paths of the ring and the casing of the male fitting, of the ring of the female fitting relative to their respective cylindrical bodies and the force of the resilient return means determine the kinematics of opening and closing the spherical closure elements as well as that of the second circuit for gathering gas for example.
Thus, as to the transfer of evaporable fluids, whether it is a matter of respecting the environment, or of the safety of people and materials, or whether it is a matter of quick operation or avoiding for military apparatus (armored, helicopters) the radar signature of refueling at night or in fog, the connection according to the invention permits collecting the gas without requiring an implantation of a loop having to be provided for the connection, as was previously the case.
For these applications, the connection according to the invention permits any maneuver of transfer involving collection of gases, this degassing taking place even when filling has not begun and ending only after filling has been completed.
In the case of automotive competition, the connection according to the invention permits gravity refuelling whilst ensuring filling carried out in record time and suitable degassing, whilst protecting the operators, the vehicles as well as the pilots, which permits better controlling the numerous requirements for successive refueling during endurance races of the 24-hour type at Mans, for example.
The connection according to the invention thus has a direct passage velocity, a drastic reduction of weight and size of the onboard portion (female fitting), an operation according to the principle of gravity, the ability to be used under other circumstances under pressure by requiring only slight modifications, a rigorous automation (the connection follows an invariable sequence), maximum performance, and which ensures simultaneously the functions: of transferring combustible in laminar flow, according to xcfx8633 m/m, (855 m/m2) for example, degassing of the gas tank under static conditions by a quasi-rectilinear passage which offers a passage cross-section of about 1700 m/m2, for example, the recovery of the gas is in static condition requiring a cross-section 1.5 times that of the supply.
Responding to the dead man principle and to the concept of gravity, the connection according to the invention satisfies all the requirements, whether in terms of effectiveness, reliability, safety or ergonomics.
According to a pre-established automatic and invariable sequence, the connection according to the invention guarantees centering and blind engagement, by peripheral guiding of the trumpet cone provided on the male fitting, a seating (and unseating) without risk of wedging, mechanical alignment of the components because of the oscillation of the sleeve and of the cylindrical ring within the female fitting, the automatic opening of the degassing openings then, consecutively, the opening of the closure of the gas tank, finally, the opening of the closure of the refueling male fitting, and conversely, the refilling having been accomplished and according to said sequence, the readability about 360xc2x0, of a possible reflux resulting from an overfill, and by disengagement, the closing of the closure of the refilling fitting (supply), the residual flow of the interface into the reservoir (automobile), the closing of the closure of the female fitting of the gas tank and then the end of degassing, finally the separation of the two fittings, even as a result of an abrupt startup.
It is to be noted that after overfilling, the connection according to the invention permits manual purge of the degassing circuit.